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International Journal of Pharmaceutics Jun 2024Vaccines based on protein antigens have numerous advantages over inactivated pathogens, including easier manufacturing and improved safety. However, purified antigens...
Vaccines based on protein antigens have numerous advantages over inactivated pathogens, including easier manufacturing and improved safety. However, purified antigens are weakly immunogenic, as they lack the spatial organization and the associated 'danger signals' of the pathogen. Formulating vaccines as nanoparticles enhances the recognition by antigen presenting cells, boosting the cell-mediated immune response. This study describes a nano-precipitation method to obtain stable protein nanoaggregates with uniform size distribution without using covalent cross-linkers. Nanoaggregates were formed via microfluidic mixing of ovalbumin (OVA) and lipids in the presence of high methanol concentrations. A purification protocol was set up to separate the nanoaggregates from OVA and liposomes, obtained as byproducts of the mixing. The nanoaggregates were characterized in terms of morphology, ζ-potential and protein content, and their interaction with immune cells was assessed in vitro. Antigen-specific T cell activation was over 6-fold higher for nanoaggregates compared to OVA, due in part to the enhanced uptake by immune cells. Lastly, a two-dose immunization with nanoaggregates in mice induced a significant increase in OVA-specific CD8 T splenocytes compared to soluble OVA. Overall, this work presents for the first time the microfluidic production of lipid-stabilized protein nanoaggregates and provides a proof-of-concept of their potential for vaccination.
PubMed: 38945464
DOI: 10.1016/j.ijpharm.2024.124404 -
The Science of the Total Environment Jun 2024The energy consumption of up to 90 % of the total power input in the anodic oxygen evolution reaction (OER) slows down the implementation of electrochemical CO...
The energy consumption of up to 90 % of the total power input in the anodic oxygen evolution reaction (OER) slows down the implementation of electrochemical CO reduction reaction (CORR) to generate valuable chemicals. Herein, we present an alternative strategy that utilizes methanol oxidation reaction (MOR) to replace OER. The iron single atom anchored on nitrogen-doped carbon support (Fe-N-C) use as the cathode catalyst (CORR), low-loading platinum supported on the composites of tungsten phosphide and multiwalled carbon nanotube (Pt-WP/MWCNT) use as the anode catalyst (MOR). Our results show that the Fe-N-C exhibits a Faradaic selectivity as high as 94.93 % towards CORR to CO, and Pt-WP/MWCNT exhibits a peak mass activity of 544.24 mA mg, which is 5.58 times greater than that of PtC (97.50 mA mg). The well-established MOR||CORR reduces the electricity consumption up to 52.4 % compared to conventional OER||CORR. Moreover, a CO emission analysis shows that this strategy not only saves energy but also achieves carbon neutrality without changing the existing power grid structure. Our findings have crucial implications for advancing CO utilization and lay the foundation for developing more efficient and sustainable technologies to address the rising atmospheric CO levels.
PubMed: 38945233
DOI: 10.1016/j.scitotenv.2024.174288 -
Mymensingh Medical Journal : MMJ Jul 2024Antibiotics' usefulness is threatened by multi-drugs resistance in harmful microorganisms because of abuse and regulatory problems. Emerging microbes, resistance...
Antibiotics' usefulness is threatened by multi-drugs resistance in harmful microorganisms because of abuse and regulatory problems. Emerging microbes, resistance mechanisms and antimicrobial drugs all require extensive investigation. Evaluation of the in vitro antibacterial activity of Methanolic extracts isolated from Black pepper seeds (Piper nigrum L.) against two infection causing pathogens, Gram-positive Staphylococcus aureus and Gram-negative Pseudomonas aeruginosa. From July 2022 and June 2023, this experimental study was conducted at the Mymensingh Medical College's Department of Pharmacology and Therapeutics in conjunction with the Department of Microbiology. The solvents Methanol and 10.0% Di-Methyl Sulfoxide (DMSO) were used to make the extract. Using the disc diffusion and broth dilution methods, the antibacterial activity of methanolic extract of black pepper seeds (MBPE) was evaluated at various doses. Using the broth dilution procedure, the conventional antibiotic Ciprofloxacin was utilized, and the outcome was contrasted with that of Methanol extracts. Methanolic extract of black pepper seeds (MBPE) at seven distinct concentrations (100, 80, 60, 40, 20, 10 and 5mg/ml) were utilized, then later in chosen concentrations as needed to confirm the extracts' more precise margin of antimicrobial sensitivity. At 80mg/ml and above doses of the MBPE, it had an inhibitory impact against the aforementioned microorganisms. For Staphylococcus aureus and Pseudomonas aeruginosa the MIC were 60 and 70mg/ml in MBPE respectively. As of the MIC of Ciprofloxacin was 1μg/ml against Staphylococcus aureus and 1.5μg/ml for Pseudomonas aeruginosa. In comparison to MICs of MBPE for the test organisms, the MIC of Ciprofloxacin was the lowest. This study clearly shows that Staphylococcus aureus and Pseudomonas aeruginosa are sensitive to the methanolic extract of black pepper seeds' antibacterial properties.
Topics: Piper nigrum; Pseudomonas aeruginosa; Plant Extracts; Staphylococcus aureus; Seeds; Anti-Bacterial Agents; Microbial Sensitivity Tests; Methanol
PubMed: 38944702
DOI: No ID Found -
Chemistry & Biodiversity Jun 2024This work aims to describe the morpho-anatomy and determine the mineral composition of H. muticus L. subsp. falezlez seed, and investigate the influence of extraction...
This work aims to describe the morpho-anatomy and determine the mineral composition of H. muticus L. subsp. falezlez seed, and investigate the influence of extraction solvents (hexane, petroleum ether, chloroform and methanol) on contents of total phenolic (TPC) and flavonoid (TFC) and the antioxidant activity (DPPH, ABTS, reducing power and phenanthroline). The mineral content analysis revealed the presence of different elements. The results indicated that the seed extract obtained by methanol exhibited the highest yield and TPC (82.07%, 27.14 ± 2.2 µg GAE/mg), while the chloroform extract had the maximum TFC (24.63 ± 0.4 µg QE/mg). In addition, all seed extracts showed excellent performances on DPPH scavenging activity. However, methanolic extract was the most effective extraction solvent for scavenging ABTS free radicals (IC50 <12.5 µg/mL). Chloroform and petroleum ether extracts were the most potent in phenanthroline activity. GC-MS analysis identified 27 phytochemical compounds in all extracts and 16 compounds were identified by HPLC/DAD analysis of the methanolic extract. The multivariate analysis results highlighted the influence of solvents on the phenolic composition and antioxidant activity of seed extracts. The results suggest that H. muticus L. seeds can be a promising source enriched with bioactive constituents for application in the pharmaceutical industry.
PubMed: 38943603
DOI: 10.1002/cbdv.202401026 -
Langmuir : the ACS Journal of Surfaces... Jun 2024Methylammonium lead halide perovskites with highly efficient pure-color or white-light generation have gained increasing scientific interest and promote the development...
Methylammonium lead halide perovskites with highly efficient pure-color or white-light generation have gained increasing scientific interest and promote the development of a great commercial opportunity in displays, lighting, and other applications. However, the poor stabilities, lead toxicity, and unfriendly solvents and ligands in the growth process severely restrict their commercial application. Here, we proposed a green method for preparing uniform and stable polymer-encapsulated photoluminescence (PL) tunable CHNHPbBrCl NC thin films at room temperature. Utilizing the swelling effect between alcohol compounds and organic polymers and the ionization of NaCl in methanol solution, the anion exchange process can be achieved rapidly within 7 min. Moreover, the PL wavelengths of the CHNHPbBrCl NCs films were precisely tuned with steps as fine as 2 nm. Experimental results showed that NaCl dissolved in methanol solution can form Cl(CHOH), which brings ionized Cl into the polymer-encapsulated CHNHPbBr NCs film for CHNHPbBrCl NCs film growth. Based on the swelling and anion exchange dynamics, a modified NaCl-CHOH-MABr solution system was developed to trigger CHNHPbBrCl NCs film PL emission tuning from 528 to 463 nm with several-fold intensity enhancement. The realization of precisely controlled photoluminescence from the perovskite nanocrystal film would have wide applications in the optical and imaging fields.
PubMed: 38943597
DOI: 10.1021/acs.langmuir.4c01505 -
Science Bulletin Jun 2024
PubMed: 38942697
DOI: 10.1016/j.scib.2024.06.006 -
Biomedicine & Pharmacotherapy =... Jun 2024This study investigated the chemical constituents, antioxidant potential, and in vitro and in silico antidiabetic activity of Gymnema sylvestre. Column chromatography...
This study investigated the chemical constituents, antioxidant potential, and in vitro and in silico antidiabetic activity of Gymnema sylvestre. Column chromatography and spectroscopic techniques identified twelve compounds from the methanol extract, including 4 sterols (1-4), 5 triterpenoids (5-9), and 3 flavonoids (10-12). The chemophenetic significance of all compounds was also investigated. The antioxidant capacity of the extract and compounds (1-4) was evaluated using FRAP and DPPH assays. The extract exhibited strong free radical scavenging activity (IC = 48.34 µg/mL), while compounds (1-4) displayed varying degrees of efficacy (IC = 98.30-286.13 µg/mL). The FRAP assay indicated significant reducing power for both extract and compounds (58.54, 47.61, 56.61, and 49.11 mg Eq.VitC/g for extract and compounds 1 & 2, 3, and 4, respectively). The antidiabetic potential was assessed through α-amylase and α-glucosidase enzyme inhibition assays. The crude extract demonstrated the most potent inhibition (IC = 218.46 and 57.42 µg/mL for α-glucosidase and α-amylase respectively) suggesting its potential for managing postprandial hyperglycaemia. In silico studies employed molecular docking and dynamics simulations to elucidate the interactions between identified compounds and α-amylase/α-glucosidase enzymes. The results revealed promising binding affinities between the compounds and target enzymes, with compound 6 demonstrating the highest predicted inhibitory activity with -10 kcal/mol and -9.1 kcal/mol for α-amylase and α-glucosidase, respectively. This study highlights the presence of diverse bioactive compounds in Gymnema sylvestre. The extract exhibits antioxidant properties and inhibits carbohydrate-digesting enzymes, suggesting its potential as a complementary therapeutic approach for managing hyperglycaemia associated with type 2 diabetes.
PubMed: 38941896
DOI: 10.1016/j.biopha.2024.117043 -
Journal of Chromatography. B,... Jun 2024Racecadotril, an anti-secretory medication, has been used as an adjuvant in an oral rehydration therapy for children experiencing severe diarrhea. Racecadotril is...
Racecadotril, an anti-secretory medication, has been used as an adjuvant in an oral rehydration therapy for children experiencing severe diarrhea. Racecadotril is quickly converted to thiorphan, an active metabolite, after oral treatment, which mediates all subsequent activities. An efficient and rapid liquid chromatography-tandem mass spectrometry method was developed and fully validated to measure thiorphan in human plasma, using thiorphan-d7 as an internal standard. The extraction method used was protein precipitation while chromatographic separation was achieved using InertSil CN-3 (50 × 2.1 mm, 5 µm column). The assay was linear over the concentration range of 1-200 ng/ml with correlation coefficients of ≥0.9991. The intra- and inter-day precisions were less than 10.0 % for all concentrations investigated. 0.02 % aqueous formic acid and methanol (30:70 v: v) were used as mobile phases, with an analysis time of less than 1 min. This method proved stable under several conditions. The developed method worked well in a three-period pharmacokinetic bioequivalence study after a single oral administration of 100 mg racecadotril to 15 healthy Jordanian volunteers under fasting conditions.
PubMed: 38941717
DOI: 10.1016/j.jchromb.2024.124190 -
MSystems Jun 2024We use metagenome-assembled genomes (MAGs) to understand single-carbon (C1) compound-cycling-particularly methane-cycling-microorganisms in montane riparian floodplain...
Diverse and unconventional methanogens, methanotrophs, and methylotrophs in metagenome-assembled genomes from subsurface sediments of the Slate River floodplain, Crested Butte, CO, USA.
We use metagenome-assembled genomes (MAGs) to understand single-carbon (C1) compound-cycling-particularly methane-cycling-microorganisms in montane riparian floodplain sediments. We generated 1,233 MAGs (>50% completeness and <10% contamination) from 50- to 150-cm depth below the sediment surface capturing the transition between oxic, unsaturated sediments and anoxic, saturated sediments in the Slate River (SR) floodplain (Crested Butte, CO, USA). We recovered genomes of putative methanogens, methanotrophs, and methylotrophs ( = 57). Methanogens, found only in deep, anoxic depths at SR, originate from three different clades (, , and ), each with a different methanogenesis pathway; putative methanotrophic MAGs originate from within the Archaea ( Methanoperedens) in anoxic depths and uncultured bacteria (. Binatia) in oxic depths. Genomes for canonical aerobic methanotrophs were not recovered. Methanoperedens were exceptionally abundant (~1,400× coverage, >50% abundance in the MAG library) in one sample that also contained aceticlastic methanogens, indicating a potential C1/methane-cycling hotspot. . Methylomirabilis MAGs from SR encode pathways for methylotrophy but do not harbor methane monooxygenase or nitrogen reduction genes. Comparative genomic analysis supports that one clade within the . Methylomirabilis genus is not methanotrophic. The genetic potential for methylotrophy was widespread, with over 10% and 19% of SR MAGs encoding a methanol dehydrogenase or substrate-specific methyltransferase, respectively. MAGs from uncultured archaea in the . Gimiplasmatales (UBA10834) contain pathways that may allow for anaerobic methylotrophic acetogenesis. Overall, MAGs from SR floodplain sediments reveal a potential for methane production and consumption in the system and a robust potential for methylotrophy.IMPORTANCEThe cycling of carbon by microorganisms in subsurface environments is of particular relevance in the face of global climate change. Riparian floodplain sediments contain high organic carbon that can be degraded into C1 compounds such as methane, methanol, and methylamines, the fate of which depends on the microbial metabolisms present as well as the hydrological conditions and availability of oxygen. In the present study, we generated over 1,000 MAGs from subsurface sediments from a montane river floodplain and recovered genomes for microorganisms that are capable of producing and consuming methane and other C1 compounds, highlighting a robust potential for C1 cycling in subsurface sediments both with and without oxygen. Archaea from the . Methanoperedens genus were exceptionally abundant in one sample, indicating a potential C1/methane-cycling hotspot in the Slate River floodplain system.
PubMed: 38940520
DOI: 10.1128/msystems.00314-24 -
Angewandte Chemie (International Ed. in... Jun 2024Rational design of efficient methanol oxidation reaction (MOR) catalyst that undergo non-CO pathway is essential to resolve the long-standing poisoning issue. However,...
Rational design of efficient methanol oxidation reaction (MOR) catalyst that undergo non-CO pathway is essential to resolve the long-standing poisoning issue. However, it remains a huge challenge due to the rather difficulty in maximizing the non-CO pathway by the selective coupling between the key *CHO and *OH intermediates. Here, we report a high-performance electrocatalyst of patchy atomic-layer Pt epitaxial growth on CeO2 nanocube (Pt ALs/CeO2) with maximum electron-metal support interactions for enhancing the coupling selectively. The small-size monolayer material achieves an optimal geometrical distance between edge Pt-O-Ce sites and *OH absorbed on CeO2, which well restrains the dehydrogenation of *CHO, resulting in the non-CO pathway. Meanwhile, the *CHO/*CO intermediate generated at inner Pt-O-Ce sites can migrate to edge, inducing the subsequent coupling reaction, thus avoiding poisoning while promoting reaction efficiency. Consequently, Pt ALs/CeO2 exhibits exceptionally catalytic stability with negligible degradation even under 1000 s pure CO poisoning operation and high mass activity (14.87 A/mgPt), enabling it one of the best-performing alkali-stable MOR catalysts.
PubMed: 38940407
DOI: 10.1002/anie.202410545